Gas turbine engines include compressor, combustor, and turbine sections. Low Wobbe gas fuels for gas turbine engines may require higher volumetric flow for the same heat input. A loss in velocity head of a Low Wobbe gas fuel may negatively affect combustion.
U.S. Pat. No. 6,848,260 to D. North discloses a combustor for a gas turbine engine with a premix pilot fuel stage in order to reduce the emission of oxides of nitrogen from the engine. An in-service engine may be modified to add the premix pilot fuel stage by delivering premix pilot fuel to a ring manifold for tip-feeding a premix pilot fuel outlet member such as a swirler vane or fuel peg. In this manner, complex and expensive components such as the top hat, support housing and diffusion pilot burner assembly may be used without modification. Thermal stresses caused by the differential cooling of the ring manifold by the premix fuel pilot are reduced by a heat shield installed within the manifold.
The present disclosure is directed toward overcoming one or more of the problems discovered by the inventors or that is known in the art.